1. Field of the Invention
This invention relates to collapsible dish structures of the type typically used for antennae and solar reflectors. Specifically, this invention is an improved method of constructing a collapsible dish structure which utilizes hinged, rigid petals. The dish when in its deployed configuration presents a solid, smooth surface which is suitable for the collection and focusing of extremely short wavelength electromagnetic radiation including light waves.
2. Prior Art
Collapsible dish structures are well known in the art and widely used for space applications where the antenna must be stowed during launch and deployed when the spacecraft is on station in space. Because of recent requirements for the use of shorter wavelengths in the electromagnetic spectrum, as well as an increased interest in the collection and focusing of light waves in space, collapsible dish structures for space application have been required to meet stringent requirements for surface smoothness and contour control in order to minimize scattering and improve antenna gain. These requirements have resulted in an increased dependence on antennae which utilize solid panels as contrasted to mesh collapsible antenna designs which are less suitable for short wavelengths.
Prior art in such solid deployable dish antenna designs as exemplified by U.S. Pat. No. 3,715,760 successfully solved the basic problem of constructing a rigid deployable dish. However, the art in its present state is unsuitable for antennae of large diameter compared to their stowed diameter, especially when such ratios exceed approximately 2.6:1. Furthermore, collapsible dish structures of this type are susceptible to warping due to thermal gradients, especially for antennas of advanced design with large surface to weight ratios such as the subject design.